Since commit 29d2d64ed55f ("x86: Add support for more than 8 MTRRs"), the maximum number of variable range MTRRs was increased from 8 to 10, which caused a #GP exception during VESA video driver probe.
On the BayTrail platform there are only 8 variable range MTRRs. In mtrr_commit() it still uses MTRR_MAX_COUNT which should have been updated to use dynamically probed number. This fixes the boot failure seen on Intel Minnow Max board. Fixes: 29d2d64ed55f ("x86: Add support for more than 8 MTRRs") Signed-off-by: Bin Meng <bmeng...@gmail.com> --- arch/x86/cpu/mtrr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/cpu/mtrr.c b/arch/x86/cpu/mtrr.c index 5180eb0..6f095c5 100644 --- a/arch/x86/cpu/mtrr.c +++ b/arch/x86/cpu/mtrr.c @@ -158,7 +158,7 @@ int mtrr_commit(bool do_caches) /* Clear the ones that are unused */ debug("clear\n"); - for (; i < MTRR_MAX_COUNT; i++) + for (; i < mtrr_get_var_count(); i++) wrmsrl(MTRR_PHYS_MASK_MSR(i), 0); debug("close\n"); mtrr_close(&state, do_caches); -- 2.7.4